title: A critical assessment of the prognostic value of HIV-1 RNA levels and CD4+ cell counts in HIV-infected patients. The Swiss HIV Cohort Study.
abstract: OBJECTIVE
  To determine to what extent human immunodeficiency type 1 (HIV-1) RNA levels and CD4+ cell counts predict clinical outcomes in a general HIV-1-infected population.
  
  
  METHODS
  Community-based prospective study (Swiss HIV Cohort Study) including 394 HIV-1-infected patients, randomly selected from 4 strata of CD4+ cell counts (0 to < 0.05, 0.05 to < 0.20, 0.20 to < 0.50, and > or = 0.50 x 10(9)/L). Levels of HIV-1 RNA, CD4+ cell counts, and other variables were evaluated from samples collected between 1991 and 1993 for their ability to predict death and clinical progression.
  
  
  RESULTS
  Patients were followed up on average for 29 months. Baseline HIV-1 RNA levels, CD4+ cell counts, clinical stage, and beta 2-microglobulin levels independently predicted survival, whereas only HIV-1 RNA levels and CD4+ cell counts independently predicted clinical progression. Multivariate relative hazards (RHs) for death ranged from 1.0 to 5.4 across quartiles of CD4+ counts, but only from 1.0 to 1.8 across quartiles of HIV-1 RNA. For clinical progression, gradients of risk were similar for CD4+ counts (1.0-4.2) and for HIV-1 RNA (1.0-3.1). In patients with CD4+ cell counts less than 0.05 x 10(9)L, HIV-1 RNA levels predicted neither death nor clinical progression. Finally, the number of HIV-1 RNA copies per CD4+ cell was the best predictor of death (multivariate RH, 1.0-9.7 across quartiles) and clinical progression (multivariate RH, 1.0-4.1).
  
  
  CONCLUSIONS
  Levels of HIV-1 RNA and CD4+ cell counts provided independent and complementary information on clinical outcomes. The RNA/CD4+ ratio was the best single predictor. In patients who had fewer than 0.05 x 10(9)/L CD4+ cells, HIV-1 RNA levels had little prognostic value.
authors.affiliation: Laboratory of Virology, Geneva University Hospital, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Yerly
authors.forename: T V
authors.initials: TV
authors.lastname: Perneger
authors.forename: B
authors.initials: B
authors.lastname: Hirschel
authors.forename: O
authors.initials: O
authors.lastname: Dubuis
authors.forename: L
authors.initials: L
authors.lastname: Matter
authors.forename: R
authors.initials: R
authors.lastname: Malinverni
authors.forename: H
authors.initials: H
authors.lastname: Furrer
authors.forename: L
authors.initials: L
authors.lastname: Perrin
mesh_terms: D000328:Adult; D000368:Aged; D018791:CD4 Lymphocyte Count; D018450:Disease Progression; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood*; D012306:Risk; D016019:Survival Analysis; D013557:Switzerland
chemical_list: D012367:RNA, Viral